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U.S. DEPARTMENT OF THE INTERIOR

BUREAU OF LAND MANAGEMENT

Oregon / Washington

GIS Metadata


BLM OR Aerial Photography Tiles Polygon

Frequently-asked questions:


What does this data set describe?

Title:
BLM OR Aerial Photography Tiles Polygon

Abstract:
ap_boundaries_tile: Polygon feature of aerial photography image coverage for BLM aerial photo projects in the states of Oregon and Washington. Individual polygons indicate the image footprint at the nominal scale of the photography. Imagery may be captured by linear scanner or by small scale single image sensors such as satellite. This is subject to update at a future point.

  1. How should this data set be cited?

    Bureau of Land Management, Oregon State Office, 20130926, BLM OR Aerial Photography Tiles Polygon.

  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -125
    East: -116
    North: 49.5
    South: 41.5

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Beginning date: 19540701
    Ending date: 20120423
    Currentness reference:
    publication date

  5. What is the general form of this data set?

    Geospatial data presentation form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • GT-polygon composed of chains (132)
      • GT-polygon composed of chains (132)

    2. What coordinate system is used to represent geographic features?

  7. How does the data set describe geographic features?

    ap_tiles_poly_1
    OBJECTID
    Internal feature number. (Source: ESRI)
                      

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry. (Source: ESRI)
                      

    Coordinates defining the features.

    Name
    Tile Identification (Source: BLM)
                      

    Proj_name
    Project code used as a unique identifier. (Source: BLM)
                      

    PhotoTime
    Time of image exposure (Source: BLM)
                      

    District
    BLM District project is located within. (Source: BLM)
                      

    film_type
    Type of film used in project. Types of film include Black & White (B/W), Natural Color (NC), Color Infrared (CIR), Digital film flown in Red, Green, Blue (RGB). (Source: BLM)
                      

    ValueDefinition
    RGB
    3 band sensor (red, green, blue)
    RGBI
    4 band sensor (red, green, blue, near infrared)

    PhotoDate
    Date or range of dates photos were taken. (Source: BLM)
                      

    GSD
    TileID
    Unique Tile name (Source: BLM)
                      

    SHAPE_Length
    Length of feature in internal units. (Source: Esri)
                      

    Positive real numbers that are automatically generated.

    SHAPE_Area
    Area of feature in internal units squared. (Source: Esri)
                      

    Positive real numbers that are automatically generated.

    Entity and attribute overview:
    Project boundaries are in a polygon feature class, created from digital point files.

    Entity and attribute detail citation:
    The project boundary is created in ArcMap by buffering the flight lines of the project.  The buffered area around each flight line simulates the size of a line of overlapped photos, taking into consideration the scale of the photography and the length of the camera lens.  Since sidelap and endlap are required, the rows of flight line boundaries merge to form one project boundary with all interior boundaries lines dissolved.
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Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

    • Bureau of Land Management, Oregon State Office

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Corey Plank
    Bureau of Land Management
    Lead Cartographer
    P.O. Box 2965
    Portland, OR 97204
    US

    (503) 808-6145 (voice)
    cplank@blm.gov
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Why was the data set created?

This feature is intended to facilitate the location and identification of BLM flightline data in Oregon and Washington for release to BLM district personnel, other agencies, and the general public.

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How was the data set created?

  1. Where did the data come from?

  2. What changes have been made?

    Date: 20120423 (change 1 of 1)
    Footprint data is created based on sensor characteristics and flight information.

    Person responsible for change:
    Eric Hiebenthal
    Bureau of Land Management, Oregon State Office
    GIS Data Management Specialist
    P.O. Box 2965
    Portland, OR 97208
    US

    503-808-6565 (voice)
    503-808-6419 (FAX)
    ehiebent@blm.gov

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How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    Accuracy varies depending on ground terrain. Coverage is based on horizontal position and altitude information gathered in flight. Additional ground control may be used to increase accuracy.

  2. How accurate are the geographic locations?

  3. How accurate are the heights or depths?

    Not applicable.

  4. Where are the gaps in the data? What is missing?

  5. How consistent are the relationships among the observations, including topology?

    Not applicable.

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How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access constraints: PUBLIC DATA: None, these data are considered public domain.
Use constraints:
These data are provided by Bureau of Land Management (BLM) "as is" and may contain errors or omissions. The User assumes the entire risk associated with its use of these data and bears all responsibility in determining whether these data are fit for the User's intended use. The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived, and both scale and accuracy may vary across the data set. These data may not have the accuracy, resolution, completeness, timeliness, or other characteristics appropriate for applications that potential users of the data may contemplate. The User is encouraged to carefully consider the content of the metadata file associated with these data. These data are neither legal documents nor land surveys, and must not be used as such. Official records may be referenced at most BLM offices. Please report any errors in the data to the BLM office for which it was obtained. The BLM should be cited as the data source in any products derived from these data. Any Users wishing to modify the data should describe the types of modifications they have performed. The User should not misrepresent the data, nor imply that changes made were approved or endorsed by BLM. This information may be updated without notification.

Distributor 1 of 1

  1. Who distributes the data set?

    Eric Hiebenthal
    Bureau of Land Management, Oregon State Office
    GIS Data Management Specialist
    P.O. Box 2965
    Portland, OR 97208
    US

    503-808-6565 (voice)
    503-808-6419 (FAX)
    ehiebent@blm.gov

  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

    The BLM assumes no responsibility for errors or omissions. No warranty is made by the BLM as to the accuracy, reliability, or completeness of these data for individual use or aggregate use with other data; nor shall the act of distribution to contractors, partners, or beyond, constitute any such warranty for individual or aggregate data use with other data. Although these data have been processed successfully on computers of BLM, no warranty, expressed or implied, is made by BLM regarding the use of these data on any other system, or for general or scientific purposes, nor does the fact of distribution constitute or imply any such warranty. In no event shall the BLM have any liability whatsoever for payment of any consequential, incidental, indirect, special, or tort damages of any kind, including, but not limited to, any loss of profits arising out of the use or reliance on the geographic data or arising out of the delivery, installation, operation, or support by BLM.

  4. How can I download or order the data?

  5. Is there some other way to get the data?

  6. What hardware or software do I need in order to use the data set?

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Who wrote the metadata?

Dates:
Last modified: 20120423
Last reviewed: 20131021

Metadata author:
Roger Mills
Bureau of Land Management, Oregon State Office
GIS Spec
P.O. Box 2965
Portland, OR 97208
US

(503) 808-6340 (voice)
(503) 808-6419 (FAX)
r2mills@blm.gov

Metadata standard:
FGDC Content Standard for Digital Geospatial Metadata(FGDC-STD-001-1998)

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